Crate sn3193 

This Rust embedded-hal-based library is a simple way to control the SN3193 RGB LED driver. The SN3193 is a 3-channel LED driver with PWM control and breathing mode. It can drive up to 3 LEDs with a maximum current of 42 mA and is controlled via I2C. This driver is designed for the no_std environment, so it can be used in embedded systems.

Usage

Add this to your Cargo.toml:

[dependencies]
sn3193 = "0.1"

Then to create a new driver:

use embedded_hal::delay::DelayMs;
use embedded_hal::i2c::I2c;
use sn3193::SN3193Driver;

// board setup
let i2c = ...; // I2C peripheral
let delay = ...; // DelayMs implementation

// It is recommended that the `i2c` object be wrapped in an `embedded_hal_bus::i2c::CriticalSectionDevice` so that it can be shared between
// multiple peripherals.

// create and initialize the driver
let mut driver = SN3193Driver::new(i2c, delay);
if let Err(e) = driver.init() {
   panic!("Error initializing SN3193 driver: {:?}", e);
}

Features

PWM mode

The driver can set the LEDs to PWM mode. This allows you to set the brightness of each LED individually.

if let Err(e) = diver.set_led_mode(LEDModeSettings::PWM) {
   panic!("Error setting LED mode to PWM: {:?}", e);
}
// check your device wiring to know which LED is which
if let Err(e) = driver.set_pwm_levels(255, 128, 0) {
  panic!("Error setting PWM levels: {:?}", e);
}

Breathing mode

The driver can set the LEDs to breathing mode. This mode allows you to set the time it takes for the LED to ramp up to full brightness, hold at full brightness, ramp down to off, and hold at off. Each of these times can be set individually for each LED. Furthermore, the PWM levels can be set for each LED.

// set the breathing times the same for all LEDs
if let Err(e) = driver.set_breathing_times_for_led(
    LEDId::ALL,
    BreathingIntroTime::Time1p04s,
    BreathingRampUpTime::Time4p16s,
    BreathingHoldHighTime::Time1p04s,
    BreathingRampDownTime::Time4p16s,
    BreathingHoldLowTime::Time2p08s,
) {
   panic!("Error setting breathing times: {:?}", e);
}
// enable breathing mode
if let Err(e) = driver.set_led_mode(LEDModeSettings::Breathing) {
  panic!("Error setting LED mode to breathing: {:?}", e);
}

The PWM levels and breathing times can be changed at any time. The driver will update the LEDs with the new settings.

Function chaining

The driver functions return a Result that contains the driver reference in the Ok value. This can be chained together to make the code more readable.

driver.set_led_mode(LEDModeSettings::PWM)?
    .set_current(CurrentSettings::Current17p5mA)?
    .set_pwm_levels(255, 128, 0)?
    .enable_leds(true, true, true)?;

License

This library is licensed under the MIT license.

Structs

SN3193Driver

Enums

BreathingHoldHighTime

The time that the high brightness is held. The time is set in the T2 register.

BreathingHoldLowTime

The time that the low brightness is held. The time is set in the T4 register.

BreathingIntroTime

The time it takes to start breathing. The time is set in the T0 register.

BreathingRampDownTime

The time it takes to ramp down from high to low brightness. The time is set in the T3 register.

BreathingRampUpTime

The time it takes to ramp up from low to high brightness. The time is set in the T1 register.

CurrentSettings

LEDId

LEDModeSettings

LED mode settings

SN3193Error

Errors generated by the SN3193 driver